AN official report into the feasibility of a bridge or tunnel connecting Scotland to Northern Ireland has revealed the staggering cost of the project.

The Prime Minister, once a champion of the idea, had previously claimed a fixed link between the two nations would cost around £15 billion.

However a feasibility report published today (November 26) has revealed how far off this estimate was, instead putting the cost of building a bridge as high as £335bn.

The upper estimate from the Union Connectivity Review is more than 22 times higher than what Boris Johnson had said.

A tunnel, the review found, would be cheaper. It puts an upper estimate for the cost of a tunnel at £209bn. This is still almost 14 times Johnson’s £15bn estimate.

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The report says that due to the “very significant works” needed, such as the planning, design, parliamentary and legal processes, and construction, a crossing would take “nearly 30 years” to complete.

It adds: “Whilst the economic and social effects would be transformational, the costs would be impossible to justify.

“It is therefore my recommendation to Government that further work on the fixed link should not progress beyond this feasibility study.”

The report was penned by Sir Peter Hendy, the current chairman of Network Rail.

Johnson had previously touted the idea, claiming that the only issue was “political will”.

He said in 2019: "[I was talking] about building a bridge from Stranraer in Scotland to Larne in Northern Ireland - that would be very good. It would only cost about £15bn."

The National:

The sea between Stranraer and Larne offers many challenges, the report says, not least Beaufort’s Dyke, “a deep seabed trench that runs between 8 and 13km off and parallel to the Rhins of Galloway”.

“It is more than 45km in length and is approximately 3.5km wide at its broadest point.

“From World War 1 to the 1970s, in the order of a million tons of unexploded ordnance may have been dumped in Beaufort’s Dyke and the North Channel, much of it unrecorded.”

Other routes considered by the feasibility review include Holyhead in Wales to Dublin, a trio of bridges leading to and from the Isle of Man, a tunnel passing Arran and Kintyre’s southern tip, and a tunnel to Northern Ireland beginning near Lockerbie on the Scottish mainland.

The National: